SUMMARY OF QUARTERLY RESULTS OF OPERATIONS (UNAUDITED) (Details 15) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Revenue recognition
Sales	$ 340,776	$ 337,226	$ 368,609	$ 314,796	$ 369,255	$ 371,142	$ 343,830	$ 319,857	$ 1,361,407	$ 1,404,084	$ 1,301,584
Operating income (loss)	(44,055)	26,905	37,376	20,509	30,740	39,602	35,923	29,940	40,735	136,205	118,583
Interim Financial Information
Revenue recognition
Sales	340,800	337,200	368,600	314,800	369,300	371,100	343,800	319,900
Operating income (loss)	(44,100)	26,900	37,400	20,500	30,700	39,600	35,900	29,900
Unallocated corporate expenses and other
Revenue recognition
Operating income (loss)									(4,200)	(4,800)	(7,100)
Unallocated corporate expenses and other | Interim Financial Information
Revenue recognition
Operating income (loss)	(500)	(1,800)	(1,500)	(400)	(1,500)	(1,100)	(1,600)	(600)
Transportation Systems
Revenue recognition
Sales									529,500	522,200	433,100
Operating income (loss)									66,800	84,600	72,000
Transportation Systems | Interim Financial Information
Revenue recognition
Sales	131,100	134,800	142,400	121,200	131,500	126,900	135,300	128,500
Operating income (loss)	(2,700)	19,000	35,300	15,200	17,900	20,000	26,700	20,000
Mission Support Services
Revenue recognition
Sales									468,700	491,400	476,500
Operating income (loss)									(36,100)	21,100	23,900
Mission Support Services | Interim Financial Information
Revenue recognition
Sales	109,300	123,800	122,200	113,400	134,600	122,400	126,900	107,500
Operating income (loss)	(47,500)	3,600	3,600	4,200	6,100	5,900	4,600	4,500
Defense Systems
Revenue recognition
Sales									363,000	389,400	390,700
Operating income (loss)									14,200	35,300	29,800
Defense Systems | Interim Financial Information
Revenue recognition
Sales	100,500	78,600	103,900	80,000	102,900	121,500	81,300	83,700
Operating income (loss)	6,600	6,100		1,500	8,200	14,800	6,200	6,000
Other
Revenue recognition
Sales									200	1,100	1,300
Other | Interim Financial Information
Revenue recognition
Sales	$ (100)		$ 100	$ 200	$ 300	$ 300	$ 300	$ 200